Method of making ring-gear blanks



Patented May 22, 1928.

UNITED STA ES 1,670,758 PATENT OFFICE.

WILLIAM P. WITHEROW, OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR, BY ME SNE AS- SIGNMENTS, TO COLONIAL TRUST COMPANY, TRUSTEE, OF PITTSBURGH, PENNSYL- VANIA, A CORPORATION OF PENNSYLVANIA.

METHOD OF MAKING RING-GEAR BLANKS.

Application filed August 1, 1923. Serial No. $55,062.

The present invention relates broadly to metal working, and more particularly to the art of die-rolling and forging as applicable to the production of gears, such, for example, as ring gears of the character used in the automotive industry, although the utility of the invent-ion is not limited in this respect, it being also highly desirable in the making of chain;

At the present time considerable attention is being paid to the manufacture of ring gears in .an effort. to produce stronger gears at a reduced cost and in larger numbers, as

required by the increasing demand'for automobiles. One of the important problems in this art lies in the production of a blank having a proper disposition of fibres, so that the fibres in the'finished blank will extend in the required direction. Preferably such fibres should extend either radially or circumferentially, but in any case, irrespective of thedirection of extension of the fibres, it is desirable that they be as nearly uniformly disposed throughout the entire blank as possible.

In accordance with the present invention, there is provided an. improved method of making ring gear blanks in quantity and pf such material that [a ver desirable arrangement of fibres is insured. v a -In the accompanying drawings there are shown for purposes of illustration only certain-preferred embodimentsiof the present invention, it being understood that the drawings do not define the limits of my invention, as changes may obviously be made in'the construction disclosed therein without departing from the spirit of the invention or scope of my broader claims.

In the drawings,-

Figure 1 is a top plan view illustrating a portion of a connected seriesqof loopshaped blanks as formed by die-rolling;

Figure 2 is a view similar to. Figure 1, illustrating a preferred manner of separating the individual blanks; Y

Figure 3 is a top plan view illustrating a modified method of separating the blanks;

Figure 4 is a viewof a b ank such as illustrated in Figure 2, which has been worked to substantially ring sha e;

Figure 5 is a top pan view 0 a. blank which has been subjected to a forging operation;

the flash removed therefrom;- V

Figure 7 as; transversefsectional View through 'the blank illustrated in Figure 6; and

Figure Sis a side elevation illustrating a modified embodiment of theiinv'ention.

-In accordance with the present invention a leader or billet of suitable, shape having a sufficient cross-sectional: area to provide blanks having the necessary amount of Figure 6 is a similarviewyof ablank with .metal, is passed througlrdie-rolls to produce a connected serlesiof loop-shaped blanks 2, as clearly shown in Fig. 1. These loopshaped blanks are preferably spaced one from the other and connected by means of gates 3. By so shaping the die-rolls that gates between the blanks are formed,

it is possible to reduce .the thickness of the flash at all points around the blanks toa minimum and thereby facilitate the subsequent trimming of the blanks.

After a connected series of blanks of this character has been produced, they are preferably subjected to a' shearing operation which entirely removes the flash or gate from one end of each of the blanks and from the inside thereof, thereby providing the full gate on the-opposite end, as shown in Fi ure 2. This gate constitutes a tong ho d enabling an operative toeasily manipulate the blank during all of the operations which are performed thereon.

In some cases it may be desired to separate the blanks in'pairs, as illustrated in Fig. 3'whercby one blank may serve as a tong hold for the other during subsequent operations.

It will be apparent that by the die-rollin process there are provided blanks in Whic the fibers in the side of the blanks extend substantially lengthwise thereof. In the ends of the blanks, however, the fibers, while deformed somewhat due to the diesrolling operation,may beconsidered as extending partly around the .end portions and partly e'ngthwise of these end portions. Such a disposition of fibers in a finished blank, while giving all of the strength required,

would be objectionable due to the non-uniformity; In order toJovercome this objection, the blanks are preferabl rolled so as to, rovide an excess of stock in each of the en' 4 of the blanks. This excess of stock 7 insures a greater amount of working on the end portions of the blank than on the other portions, and thereby very effectively breaks up the fiber arrangement described and produces a blank in which the fiber arrangement is substantially uniform, extending around the blanks.

The individual blanks illustrated in Fig. 2 may be worked to shape by subjecting them to the action of a forging hammer, or by rolling. If a forging hammer is used, the blanks in the same heat may be shaped by dies to the form shown in Fig. 4, and then pressed by the same hammer for imparting the desired cross-sectional shape, as shown in Fig. 5. This provides a bevel face 6 on which teeth may be formed, and an inwardly projecting flange 7 for the-attachment of the gear. The flash 8 produced by this operation is then removed in any desired manner to form a clean blank, as indicated in Fig. 6, adapted to have the teeth out therein. Due to the excess of metal in the ends of the blank, these portions are subjected to a greater amount of work, thereby effectively breaking up the fiber arrangement. This insures a finished gear in which the fiber arrangement is substantially uniform.

In actual practice it has been found highly desirable in some instances to produce a connected series of blanks of the character described, and then ship the same to customers, by whom the blanks are made into finished gears. In other cases the series may be sheared or separated, as indicated in Fig. 2, and similarly handled. In this manner the die-rolling may be accomplished under given specifications at a central point and the blanks then shipped as articles of manufacture to other points for completion.

It will be understood that in accordance with this invention it is possible toproduce blanks in rapid succession with a substantially uniform distribution of stock in successive blanks. This distribution of the stock facilitates the subsequent operations on the blanks and insures disposing of the stock in such a manner that very eflicient results are obtained. In some cases the cross sectional area throughout the periphery of the blanks may be uniform or otherwise varied as may be deemed necessary.

Preferably the leader employed has a width substantially equal to the maximum width of a rolled blank, and a thickness substantially equal to the maximum thickness of the rolled blank. This facilitates the rolling operation and insures greater uniformity on successive blanks.

v I have also found that the first ste s. of the method herein described may be vantageously used in the manufacture of chains. In such cases, a connected series of blanks as shown in Figure 1, but preferably with a uniform cross sectional area throughout each blank, ma be trimmed to provide individual loop-s 'aped rings. Each pair of rings may thereafter be joined, as is customary in the art and as illustrated in Figure 8, by welding a connecting link 9 therebetween. This decreases the welding steps by one-half, and produces a chain at a much reduced cost.

Further advantages of the invention arise from the production of a blank in which the fibers are substantially uniformly disposed throughout the entire body thereof, whereby a finished blank having substantially uniform strength is insured.

I claim: I

1. In themethod of manufacturing ring gear blanks, the steps consisting in d1e-rolling a leader to produce a series of blanks separated by connecting gates, separating the connected blanks to provide a tong hold for the separated blanks, and then working the blanks to shape.

2. The method of making ring blanks which comprises rolling a leader to produce a connected series of loop-like blanks, each having side portions and curved connecting end portions gradually merging into the side portions and-having an interior web, removing the interior web, and reworking the looplike blanks to substantially circular form.

3. The method of making ring blanks which comprises rolling a leaderto produce a series of loop-like blanks, each having side portions and curved connecting end portions gradually merging into the side portions, the blanks being separated from one another by a gating and having an interior web, removing the web and reshaping the loop-like blanks. I

' 4. The method of making ring. blanks which comprises rolling a leader to produce a series of loop-like blanks, each havlng side portions and curved connecting end portions gradually mergin into the side portions, said end portions aving an excess of stock over the side portions, the blanks having an interior web, removing the web and rework ing the blanks.

5. The method of making rin'g blanks which comprises rolling a leader to produce a connected series of loop-like blanks, each having side portions and curved connect-- in end portinns graduall merging into the si e portions, the blanks eing spaced apart and connected by a gating, the string of blanks having flash on diametrically opposite sides of the strin adjacent the gating and having substantia 1y no flash along the side portions of the blanks, and reworking the blanks. Y

6. The method of making ring blanks which comprises rolling a leader to roduce a connected series of loop-like blan s, each and having substantially no flash along the side portions of the blanks, and reworking the blanks, the blanks being separated in such manner that a gating is connected toa blank for use as a tong-hold during reworking.

7. The method of making ring blanks which comprises die rolling a leader to produce a connected series of loop-like blanks each having a pair of side portions of substantially uniform cross-sectional shape lying side by side and having an interior web, the side portions being connected by generally semi-circular end portions, the end portions having substantially the same crosssectional shape as the side portions and gradually merging into such side portions, and reworking the loop-like blanks to substantially circular form.

8. The method of making rin'g blanks which comprises rolling a leader to produce a connected series of loop-like blanks, each having side portions and curved connecting end portions merging into the side portions, the blanks being spaced apart and connected by a gating,

stantially no flash along the side port-ions of the blanks, and reworking the blanks.

In testimony whereof I have hereunto set my hand.

LLIAM P. THEBOW.

the string of blanks having flash adjacent the gating and having sub 

